Make SExp a template generic.

git-svn-id: http://svn.drobilla.net/resp/llvm-lisp@20 ad02d1e2-f140-0410-9f75-f8b11f17cedd

1 files changed, 12 insertions, 10 deletions

diff --git a/ll.cpp b/ll.cpp
index e6822c6..eb8708a 100644
--- a/ll.cpp
+++ b/ll.cpp
@@ -48,21 +48,23 @@ struct Error : public std::exception {
 	const char* msg;
 };
 
+template<typename A>
+struct Exp { // ::= Atom | (Exp*)
+	Exp()                        : type(LIST)          {}
+	Exp(const std::list<Exp>& l) : type(LIST), list(l) {}
+	Exp(const A&              a) : type(ATOM), atom(a) {}
+	enum { ATOM, LIST } type;
+	A                   atom;
+	std::list< Exp<A> > list;
+};
+
 
 /***************************************************************************
  * S-Expression Lexer :: text -> S-Expressions (SExp)                      *
  ***************************************************************************/
 
 struct SyntaxError : public Error { SyntaxError(const char* m) : Error(m) {} };
-
-struct SExp {
-	SExp()                         : type(LIST)          {}
-	SExp(const std::list<SExp>& l) : type(LIST), list(l) {}
-	SExp(const std::string&     s) : type(ATOM), atom(s) {}
-	enum { ATOM, LIST } type;
-	std::string         atom;
-	std::list<SExp>     list;
-};
+typedef Exp<string> SExp;
 
 static SExp
 readExpression(std::istream& in)
@@ -461,7 +463,7 @@ ASTCall::constrain(TEnv& tenv) const
 {
 	FOREACH(TupV::const_iterator, p, tup)
 		(*p)->constrain(tenv);
-	AType*       retT = tenv.type(this);
+	AType* retT = tenv.type(this);
 	TupV texp = tuple(tenv.penv.sym("Fn"), tenv.var(), retT, NULL);
 	tenv.constrain(tup[0], new AType(texp));
 }